• Asian-Australasian Journal of Animal Sciences
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• 제15권9호
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• pp.1354-1358
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• 2002

Two hundred and ten post-larvae (PL) of Macrobrachium rosenbergii (14.5-14.9 mg) were equally distributed in two experimental groups and fed with either steam cooked or extruded pellet for a period of 60 days. Physical evaluation and growth promoting effect of both the pellets were assessed. Significantly higher (p<0.05) water stability, absorption and protein efficiency ratio (PER) were recorded in extruded pellet than the steam cooked pellet. Nutrient loss was minimum in the extruded pellet for which lower feed conversion ratio (FCR) (p<0.05) was recorded in this group. However, weight gain, relative growth and specific growth rate (SGR) in both the groups were not significantly different (p>0.05). Although insignificant (p>0.05) but higher amylase activity was recorded in steam pellet fed group. Survival was not affected by feeding either of the diets.

• 수산해양교육연구
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• 제20권1호
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• pp.90-94
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• 2008

Growth and water quality in Japanese eel, Anguilla japonica ($6.0{\pm}0.9g$) fed extruded and paste type diets were compared for 8 weeks. Fish in the duplicate tanks were fed with one of three experimental diets: two different extruded pellet diets and one paste type diet. Six FRP tanks were used with stocking density of 3.6 kg per tank (3 m3). Restricted feeds (ca. 2% of body weight) were served twice daily. Weight gains were checked at the end of every two-week interval, and water qualities in terms of NH4-N and NO2-N were determined daily one hour after feeding in the morning. Water temperature, dissolved oxygen, and pH were constantly kept within the optimum range, while fifty percent of total water volume was changed daily. Eels fed the extruded pellet diets showed significantly better (P<0.05) growth performance than did eels fed the paste type diet. The amount of feed waste from the paste type diet was significantly greater than those from the extruded pellet diets (P<0.05). Ammonia (NH4-N) waste was significantly higher from the paste diet than from the extruded pellet diets (P<0.05). These results show that extruded pellet diets are better than the paste type diet for growth and water quality management in eel culture.

• 한국양식학회지
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• 제10권2호
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• pp.163-169
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• 1997

사료물성과 단백질원 배합비에 따른 조피볼락의 성장차이를 구명하기 위하여, 실험사료의 단백질원을 북양어분과 갈색어분으로 한 사료와 경제적인 측면을 고려하여 어분의 배합 비율을 낮추는 대신, 대두박, 콘글루텐 밀, 육분 및 우모분의 비율을 늘린 2종의 사료를 설계하여, 각각 EP(extruded-floating pellet, 부상사료), SP(slow-sinking pellet, 반부상사료), FP(fast-sinking pellet, 침강사료)와 MP (moist pellet, 습사료) 형태의 배합사료를 제조하였다. 평균체중 75 g의 조피볼락을 각 수조에 50마리씩 수용하여 $2(diet\times)4(diet type)\times3(replication)$ factorial design으로 15주간 사육하였다. 사육 실험한 결과, 실험사료와 사료형태에 따른 최종평균체중, 증체율, 사료효율, 사료 섭취율, 단백질 효율, 간중량비 및 내장중량비는 전혀 차이가 없는 것으로 나타났다(P>0.05). 실험 종료시의 실험 구별, 어체 부위별 일반성분 중에 사료별, 사료 형태별로 모두 간과 근육의 단백질 및 근육의 수분과 지질 함량은 실험구간별로 유의적인 차이가 없었다(P>0.05). 위와 같이 사료의 물성이나 침강 속도는 조피볼락의 성장, 영양소 이용효율, 사료 섭취율 및 체성분에 영향을 미치지 않은 것으로 나타나, 양식 현장에서 사료 형태에 관계없이 적절히 선택하여 사용할 수 있을 것으로 전망된다.

• 수산해양교육연구
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• 제25권6호
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• pp.1315-1323
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• 2013

The purpose of this research is to evaluate the effects of a commercial mixed extruded pellet(EP) and raw fish moist pellet(MP) diet on diseases prevalence and serological constituents and HSI of korean rockfish, Sebastes schlegeli grown in two commercial-scale aquaculture farms from June to December in 2009. The growth of MP-fed rockfish was slightly faster than EP-fed rockfish during experimental period, but did not show significant differences. The levels of TCHO, TG, Glucose and TP in the MP-fed rockfish group were higher than those of EP-fed group, whereas there was no significant difference in other biochemical factors of blood between two groups. In addition, bacteria and virus were not detected in both MP- and EP-fed rockfish groups, and the infection rates of gill fluke between two groups did not show clear difference. In conclusion, there was no comparable difference in growth and the health extents of one year rockfish by administration of the commercial mixed extruded pellet(EP) and raw fish moist pellet(MP) diets.

• 수산해양교육연구
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• 제21권4호
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• pp.556-561
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• 2009

This study was conducted to evaluate the laboratory formulated extruded pellet (EP) for olive flounder Paralichthys olivaceus in the East Sea. Three replicate groups of 3,200 fish per each tank (initial weight of $28.1{\pm}0.2g$) were fed one of the two EPs (EP and CEP) and Moist pellet (MP) for 16 months in a commercial farm (Pohang, Korea). Survival was not significantly affected by experimental diets (P>0.05). Weight gain and specific growth rate of fish fed the EP were not significantly different from those of fish fed the MP, but that of fish fed CEP was significantly lower than that of fish fed EP and MP (P<0.05). Feed efficiency and protein efficiency ratio of fish fed the EP was significantly higher than those of fish fed MP (P<0.05), but not significantly different from those of fish fed CEP (P>0.05). The Contents of moisture, crude protein and crude lipid in the dorsal muscle were not significantly different among all groups (P>0.05). These results clearly indicated that the laboratory formulated extruded pellet used in this study can be developed to replace the moist pellet without affecting any growth performance of olive flounder in the commercial farm feeding trail.

• 한국수산과학회지
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• 제45권6호
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• pp.679-685
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• 2012

A study was carried out to observe the effects of feed types on the growth, feed preference, and enteric feed transition rate of juvenile starry flounder, Platichthys stellatus for 45 days. Fifty fish (avg. 135 g) were stocked each in replication, and fed a commercial extruded pellet diet (EP, 45% protein) and a moist pellet diet (MP, 65% raw mackerel+35% feed powder in wet basis), respectively. The MP presented the higher performance than that of the EP on the feed efficiency ($68.3{\pm}0.9%$ for EP and $92.3{\pm}4.3%$ for MP) and the specific growth rate ($1.07{\pm}0.07$ for the EP and $1.20{\pm}0.05%$ for the MP). In contrast, the EP showed the higher feed preference in terms of the daily feed intake ($1.57{\pm}0.08%$ for the EP and $1.30{\pm}0.01$ for the MP) and the ad libitum feeding rate after a fast of 72 hours (1.73% for the EP and 1.35% for the MP). The feed transition rate through intestinal canals decreased exponentially in both the EP and the MP, showing the faster transition rate with the EP. In the result, starry flounder appeared to have the better feed preference to the EP, but have the higher feed efficiency and growth performance to the MP.

• 수산경영론집
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• 제38권1호
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• pp.1-17
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• 2007

This study is aimed at investigating optimum level of payments in the direct payment program for aquaculture extruded pellets both theoretically and practically by analyzing the effects on production and income in accordance with Green Box conditions of WTO Agreement on Agriculture. In particular, by analyzing both effects on production and income, it evaluates and compares payments affecting to the level of production and income, respectively. Analysis results indicate that the optimum level of payments in the direct payment program for aquaculture extruded pellets is determined by the growth rate of farmed fish, farming period, price and volume of extruded pellets, and additional amount of cost increase and decrease. Suppose that growth rates of farmed fish by extruded pellets(EP) and raw fish - based moist pellets(MP) are the same, it reveals the optimum level of payment should be lowered from the current level of payment. However, when the growth rate of farmed fish by EP is lower than that by MP, the optimum level of payment should be raised from the current level and total amount of payments by area should be increased as well.

• 한국양식학회지
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• 제21권2호
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• pp.107-110
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• 2008

본 연구에서는 육성기 조피볼락 사육용으로 부상배합사료의 효과를 조사하기 위하여 평균 체중 112 g의 조피볼락을 8개월간 사육하였다. 실험사료로 4종류의 부상배합사료를 준비하여 1일 1회 만복으로 공급하였다. 사육실험 결과, 생존률은 모든 실험구에서 100%로 양호하였다. 성장률, 사료효율, 단백질효율, 사료섭취율 및 간중량지수 모두 각 실험구간에 유의한 차이가 없었다. 사육실험 종료시, 전어체와 간의 일반성분도 모든 실험구간에 차이가 없었다. 이상의 결과로 볼 때, 본 연구에 사용된 실험사료 조성은 육성기 조피볼락 양식을 위한 실용사료의 조성으로 사용하여도 좋을 것으로 판단된다.

• 한국수산과학회지
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• 제46권3호
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• pp.282-286
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• 2013

This study was conducted to compare extruded pellets (EP) and soft extruded pellets (SEP) with a raw fish-based moist pellet (MP) diet on the growth and flesh quality of Korean rockfish Sebastes schlegeli. Three groups of 20,000 fish (initial mean weight 133 g) per net-cage ($6{\times}12{\times}7m$) were fed commercial EP, SEP or MP for 16 months. The survival of fish fed SEP was higher than those of fish fed EP or MP. The highest growth performances were observed in the mean weight gain, total weight gain, and feed efficiency of fish fed MP, followed by those fed EP and SEP. Among the fish fed on extruded pellets, the total weight gain of fish fed SEP was higher than that of those fed EP, while fish fed EP grew faster than those fed SEP. No notable differences in body composition, sensory scores or textural properties of the dorsal muscle were observed in fish fed on EP, SEP or MP. Thus, it is suggested that extruded pellets, rather than raw fish-based moist pellets, could be fed to Korean rockfish without compromising flesh quality.

• 한국기계가공학회지
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• 제11권6호
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• pp.152-157
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• 2012

This study investigates compressive strength of ice pellet strip which is potential medium for Natural Gas Hydrate(NGH) extruded from die holes of Twin-roll Press for Continuous Pelletizing(TPCP). Recently, the prototype of TPCP is newly developed where ice powder is continuously fed and extruded into strip-type pellet between twin rolls. The system is specifically designed for future expansion towards mass-production of ice pellet strips or solid form of natural gas hydrate. It is shown that the compressive strength of pellet strip heavily depends on factors in extrusion process such as disk size, surface smoothness, ring size, taper shape, feeding mechanism, and rotational speed. Here, the mechanism of TPCP, along with compressive strength of pellets is discussed in terms of its feasibility for producing NGH pellets in the future.